Devices are known for deactivating one or more engine valves at times during lower engine power requirements to provide fuel economy. These take several forms. For example, one known design utilizes a zero lift cam lobe that can be made operative to deactivate a particular valve or valves when desired. Another type utilizes a sliding sleeve assembly and different pad members for selectively deactivating a particular valve. A third type uses several cams to actuate a number of valves, one cam lobe being higher than others and activated when desired to disable the operation of a pair of valves. Another construction uses locking pins in cooperation with low and high speed rocker arms in side-by-side relationship to disable particular engine valves. None of the above designs provides a finger follower rocker arm construction having valve deactivation means wholly contained within the rocker arm, and one which simply can be substituted for a conventional finger follower type rocker arm to provide activation or deactivation of its associated engine valve as desired.
The prior art valve deactivating designs are not the integral type replacements for conventional roller finger follower rocker arms, are more complicated and expensive to manufacture, and generally require much more precise machining procedures.